Dcbx Port Roles - Dell Force10 MXL Blade Configuration Manual

DCBX Port Roles

Use the following DCBX port roles to enable the auto-configuration of DCBX-enabled ports and
propagate DCB configurations learned from peer DCBX devices internally to other switch ports:
• Auto-upstream: The port advertises its own configuration to DCBX peers and receives its
configuration from DCBX peers (ToR or FCF device). The port also propagates its configuration to
other ports on the switch.
The first auto-upstream that is capable of receiving a peer configuration is elected as the configuration
source. The elected configuration source then internally propagates the configuration to auto-down-
stream ports. A port that receives an internally propagated configuration overwrites its local configura-
tion with the new parameter values.
When an auto-upstream port (besides the configuration source) receives and overwrites its configura-
tion with internally propagated information, one of the following actions is taken:
• If the peer configuration received is compatible with the internally propagated port configuration,
the link with the DCBX peer is enabled.
• If the received peer configuration is not compatible with the currently configured port
configuration, the link with the DCBX peer port is disabled and a syslog message for an
incompatible configuration is generated. The network administrator must then reconfigure the peer
device so that it advertises a compatible DCB configuration.
The configuration received from a DCBX peer or from an internally propagated configuration is not
stored in the switch's running configuration.
On a DCBX port in an auto-upstream role, the PFC and application priority TLVs are enabled. ETS
recommend TLVs are disabled and ETS configuration TLVs are enabled.
• Auto-downstream - The port advertises its own configuration to DCBX peers but is not willing to
receive remote peer configuration. The port always accepts internally propagated configurations from
a configuration source. An auto-downstream port that receives an internally propagated configuration
overwrites its local configuration with the new parameter values.
When an auto-downstream port receives and overwrites its configuration with internally propagated
information, one of the following actions is taken:
• If the peer configuration received is compatible with the internally propagated port configuration,
the link with the DCBX peer is enabled.
• If the received peer configuration is not compatible with the currently configured port
configuration, the link with the DCBX peer port is disabled and a syslog message for an
incompatible configuration is generated. The network administrator must then reconfigure the peer
device so that it advertises a compatible DCB configuration.
The internally propagated configuration is not stored in the switch's running configuration.
On a DCBX port in an auto-downstream role, all PFC, application priority, ETS recommend, and ETS
configuration TLVs are enabled.
• Configuration source - The port is configured to serve as a source of configuration information on the
switch. Peer DCB configurations received on the port are propagated to other DCBX auto-configured
ports. If the peer configuration is compatible with a port configuration, DCBX is enabled on the port.
On a configuration-source port, the link with a DCBX peer is enabled when the port receives a DCB
configuration that can be internally propagated to other auto-configured ports.
The configuration received from a DCBX peer is not stored in the switch's running configuration.
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